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The Use of High-resolution Infrared Thermography (HRIT) for the Study of Ice Nucleation and Ice Propagation in Plants
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Comentario a "La supervivencia glacial de los árboles boreales en el norte de Escandinavia"
Hilary H Birks1, Thomas Giesecke, Godfrey M Hewitt
1Department of Biology, University of Bergen, Bergen, Norway. hilary.birks@bio.uib.no
Science (New York, N.Y.)
|November 10, 2012
Resumen
Este estudio cuestiona la evidencia de la supervivencia de Pinus y Picea en Escandinavia durante el último período glacial. Las limitaciones metodológicas y explicaciones alternativas sugieren que estos árboles pueden haberse extinguido después del calentamiento glacial.
Área de la Ciencia:
- La paleobotánica es la paleobotánica.
- Ciencia Cuaternaria La ciencia cuaternaria es la ciencia cuaternaria.
- Genética La genética.
Sus antecedentes:
- Se debate la supervivencia de Pinus y Picea en el norte de Escandinavia durante el último período glacial.
- Estudios anteriores proponen refugios glaciales para estos taxones.
Objetivo del estudio:
- Evaluar críticamente la evidencia presentada para la supervivencia glacial de Pinus y Picea en el norte de Escandinavia.
- Proponer explicaciones alternativas para los datos genéticos observados.
Principales métodos:
- Revisión de las metodologías utilizadas en estudios anteriores.
- Análisis de la posible contaminación en los datos genéticos.
- Consideración de los datos paleoecológicos y paleoclimatológicos.
Principales resultados:
- Metodologías empleadas por Parducci et al. no descartan la contaminación de la muestra.
- Falta de hábitats glaciales adecuados para Pinus y Picea en los refugios propuestos.
- La evidencia sugiere la extinción de estos taxones después de la deglaciación.
Conclusiones:
- La evidencia presentada para la supervivencia glacial de Pinus y Picea en el norte de Escandinavia no es convincente.
- Las hipótesis alternativas, incluida la colonización y extinción posdeglacial, explican mejor la distribución de marcadores genéticos como el haplotipo A. de Picea.
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